Figure 6: Quaternary contacts alter deuterium exchange: Comparison of HDXMS of unassembled E-protein with E-protein from DENV particles.

RFU of unassembled DENV2 E-protein (a) at 28 °C for time points (1, 2, 5, 10 and 60 min) and DENV1 E-protein (b) at 28 °C for deuterium labelling time point of 1 min are shown as a modified mirror plot. E-protein peptides are listed from N- to C-terminus (X-axis). Error bars for each peptide are shown as shaded regions along the X-axis and are colour coded according to the RFU plots. The s.e. for a given peptide represents the sum of the single sigma s.d.'s over all the time-points from three independent HDXMS measurements. RFU after 1 min of deuterium exchange from unassembled DENV2 (c) and DENV1 (d) E-protein is overlaid onto the respective E-protein structures (PDB ID:1OAN, 4CCT). RFU is colour coded according to key. The range has been maintained the same as in for better visual comparison between virion and unassembled E-protein. Comparison of deuterium uptake of identical peptides between viral E-protein and unassembled E-protein from DENV2 (e) and DENV1 (g). SD represents the single s.d. of deuterium uptake for each listed peptide and differences in deuterium uptake were calculated by subtracting deuterium uptake of unassembled E-protein peptides with viral E-protein peptides at 28 °C. Peptides showing large differences in deuterium exchange (indicated in blue) between unassembled and viral E-proteins in DENV2 and DENV1 are mapped onto a raft of three parallel E-dimers (f). Black arrows indicate the regions where the largest magnitude differences in deuterium exchange between unassembled E-protein and viral E-protein were observed.